Composite board and process of making same



Jan. 1, 1924 1,479,044

I 1... KIRSCHBRAUN COMPOSITE BOARD AND PROCESS OF MAKING SAME Filed Aug.16. 1922 Jurface y Patented Jan. ll, I924.

1. KIRSCRAUN, OF CHICAGO, ILLINOIS.

COMPOSITE BOARD AND PROCESS OF MAKING SE.

Application filed August 16, 1922. Serial No. 582,310.

To all w/wm it may concern:

Be it known that I, LESTER KmsoriBRAUN,

, a citizen of the United States, residin in the city of Chicago, countyof Cook, tate of Illinois, have invented certain new and usefulImprovements in Composite Board and Processes of Makin Same, of whichthe following is a speci cation.

This invention relates to improvements in boards and is particularlyadvantageous in the manufacture of wall-boards. One of the objects ofthe invention is to produce a structure which is very strong and stiffand will not take up moisture and be subject to expansion, contractionor abutment.

The invention may be carried out as follows:

An emulsion of asphalt, colloidal clay and water may first be formed inthe manner described in my prior Patent No. 1,-

' 417,835. This emulsion may then be mixed with fibre. To this mixturemay then be added infusorial or diatomaceous earth- The emulsion ispreferably relatively thick and pasty, of a character such as comes fromwater may be added dry fibre. This dry fibre is thoroughly macerated inthe emulsion and the dry fibre takes up or soaks up water from theemulsion. This of course makes a thicker; mixture than the emulsionalone. To thismixture or simultaneous with the addition of the fibre isadded dry infusorial earth in more or less powdered form. This dry earthis thoroughly mixed with the other ingredients and it will take up stillmore water and still further thicken the mass. The result is to producea more or less pulverulent granular composition without much cohesionand of such a consistency that it can be loosely and readily spread in asheet or other form.

The percentages of the various ingredients may for example be asfollows:

The final composition may have about three to five parts of fibre,forty-five parts of infusorial earth, ten parts of clay and forty partsof asphalt, all by weight. It is understood, however, that thesepercentages may be varied widely.

The composition thus formed may then be spread over a sheet ofpapermounted on a table or other movable support and a second layer of paperplaced on the top of the sheet thus formed, and the three layers, i. e.,the two layers ofpaper and the layer of the composition above describedpressed together to form a unitary structure, it being understood thatthe outer layers'of paper Wlll firmly adhere to the inner compositionlayer.

During the pressing operation it may be desirable to more effectivelyremove water. The outer layers of paper may be 15 to 30 points caliperand the inner-midst compositlon layer may be seventy-five to one hundredand twenty-five points caliper.

An invention may becarried out in which the fibre may be materiallyreduced or entirely dispensed with.

An invention may be carried out in the manner first described in which,instead of using infusorial earth, ground cork, sawdust,

.or a mixture of both and with or without infusorial earth may be used.It may be here statedthat it is desirable to produce a board that 1s notmerely strong and weather resisting as above referred to, but is alsolight in weight.

In carrying out the invention or inven-a tions in any of the mannersabove described, it is desirable that the composition when sheeted, besubjected to high pressure in order to consolidate it and make as densea product as possible, Also, it may be desirable to run the formed sheetthrough steamheated rollers to effectively remove all moisture, but itmay be noted that the percentage of water in the final composition is,relative to the other constituents, relatively small. In factthe'mixture might be air-dried before it is sheeted so as to reduce thewater content to a minimum.

It is to be noted that it is desirable to use a pitch of sufficientlyhard character, as for example, asphalt to from 160 Fahrenheit to 175Fahrenheit and such a percentage of colloidal clay so as to produce asufliciently fine dispersion to the asphalt as to permit a relatively.large percentage of the water being transferred to the fibre andinfusorial earth without breaking down the emulsion and making anundesirable gummy mass.

Instead of making wallboard in the manner above described, alinoleum-like product may be formed in which the composition referred tois spread over burlap and pressed thereto and then dried as heretoforedescribed. This results in making an impermeable wear-resisting surface,capable of being painted or otherwise colored, but in such case it maybe desirable to use for example, linseed or other oxidizable oil basesinstead 0t asphalt.

ll claim as my invention:

l. A Waterproof board consisting of a plurality of plies, one of saidplies c0nsisting essentially of bitumen or pitch, infuserial earth andfibre.

2. A water roof board consisting of a plurality of p ies, one of saidplies consisting essentially of bitumen or pitch, andini'Eusorial'earthJ 3. A. board consisting of outer plies and an innercore, said inner core containing bitumen, fibre and a light-weightporous ma terial. I

4:. A process of making a board consisting in forming an emulsion ofpitch, clay and Water, macerating in said emulsion relatively dry fibreand dry porous material, and forming this composition into a sheetbetween two outer covering plies.

5. A process of making a board consisting in making an emulsion ofbitumen or pitch, water and an emulsifying agent adding theretorelatively dry fibre and infusorial earth and forming this compositioninto a sheet between tWo outer covering plies.

LESTER KIRSGHBRAUN.

